Transcript Disentangling Resonant and Non

Resonant and Non-resonant Phenomena in RIXS
 Spectroscopic aspects of RIXS
 Resonant and non-resonant
 Integrated 2p3d RIXS (FY detection)
 Removing the obscuring silent majority
resonant inelastic x-ray scattering/spectroscopy
2p XAS: 2p3d integrals & 2p spin-orbit coupling
3d
<2p3d|1/r|2p3d>
2p3/2
2p1/2
Phys. Rev. B. 42, 5459 (1990)
CTM4XAS (semi-empirical)
2p3s RIXS of CaF2
3d0 → 2p5 3d1 → 3s1 3d1
Rubensson et al. Phys. Rev. B. 49, 1507 (1994); Phys. Rev. B. 53, 7099 (1996)
2p3s RIXS of CaF2
Is interference important?
If not RIXS = XAS * XES
Rubensson et al. Phys. Rev. B. 49, 1507 (1994); Phys. Rev. B. 53, 7099 (1996)
2p3s RIXS of CaF2
Is interference important?
If not RIXS = XAS * XES
Rubensson et al. Phys. Rev. B. 49, 1507 (1994); Phys. Rev. B. 53, 7099 (1996)
La 4d5p RIXS: importance of interference
4f0 4d9 4f1[3D1]
 5p1 4f1
Phys. Rev. Lett. 103, 137401 (2009)
La 4d5p RIXS: importance of interference
4f0 4d9 4f1[3D1]
 5p1 4f1
Resonant XES spectra
change within
a single resonance
Phys. Rev. Lett. 103, 137401 (2009)
La 4d5p RIXS: importance of interference
3D
1
pre-edge interferes
with tail of delayed onset
at 17 eV
Phys. Rev. Lett. 103, 137401 (2009)
2p3s RIXS of CaF2
3d0 → 2p5 3d1 → 3s1 3d1
Rubensson et al. Phys. Rev. B. 49, 1507 (1994); Phys. Rev. B. 53, 7099 (1996)
Resonant and non-resonant
XAS * XES
XPS * XES
Phys. Rev. B. 53, 7099 (1996)
Resonant and non-resonant
XPS * XES
Glatzel et al., Phys. Rev. B. 64, 045109 (2001)
Resonant and non-resonant
XAS * XES
XPS * XES
Phys. Rev. B. 53, 7099 (1996)
‘non-resonant peak’ only visible at resonance
Ground state:
3d8 + 3d9 + 3d10
XAS main: 3d9
XAS CT: 3d10
XPS: <1% 3d10
Finazzi et al. PRB 59, 9933 (1999)
2p3d RIXS of NiO
S
‘spin-flip’
dd
MS
spin-flip
Phys. Rev. B. 57, 14584 (1998)
2p3d RIXS XES of CoO
Van Schooneveld et al. J. Phys. Chem. C. 116, 15218 (2012)
CTM4RIXS (semi-empirical)
(crystal fields, exchange field, spin-orbit, [charge transfer])
CTM4RIXS by P. Glatzel, E. Stavitski et al.
Fluorescence Yield = integrated 2p3d RIXS
• FY-XAS ≠ XAS
• L2 edge increases & High-energies increase
• Sum rules break down
• Strong polarization dependence
Kurian J. Phys. Cond. Matt. 24, 435602 (2012)
Dips and peaks in FY-XAS
Nature Chem. 4, 766 (2012)
Problem: XAS measures average of all atoms
Nanoscale chemical imaging of a working catalyst
Normalized Absorption
1 bar, 350 C
0
Fe
Fe3O4
1.0
0.5
0.0
710
720
730
Normalized Absorption
X-Ray Energy (eV)
*
1.0
*
0.5
Carbon K-edge
0.0
280
290
300
310
X-Ray Photon Energy (eV)
de Smit et al. Nature 456, 222 (2008); Angew. Chem. 48, 3632 (2009)
Problem: XAS measures average of all atoms
• 2p XAS under in-situ conditions
• Measure different valences in one spectrum
• GOAL: measure spectra for each valence separate
Valence selective XAS
Glatzel et al. Inorg. Chem. 41, 3121 (2002)
Removing the silent majority
2p XAS of Co2+ and Co3+
Removing the silent majority
2p XAS of Co2+ and Co3+
Removing the silent majority
2p RIXS of Co2+ and Co3+
Removing the silent majority
2p RIXS of Co2+ and Co3+
Acknowledgements
Utrecht University:
Matti van Schooneveld (Mülheim)
Reshmi Kurian
Piter Miedema (Bessy)
Emiel de Smit (Exxon)
Fernando Morales (Topsoe)
Eli Stavitski (CLS)
Thorsten Schmidt (SLS)
Pieter Glatzel (ESRF)